The end of the last Ice Age brings warmer, wetter conditions to the region that will become southeastern Anatolia, allowing wild cereals and game to flourish.
Mobile hunter-gatherer bands begin seasonally converging on a limestone hilltop near the Harran plain, an early social and possibly ritual focal point.
The oldest known megalithic structures at Göbekli Tepe, massive T-shaped limestone pillars arranged in circular enclosures, are erected by cooperating hunter-gatherer groups.
Evidence of large-scale food preparation, including massive stone vessels and butchered wild animal remains, points to communal feasts accompanying construction work.
Nearby communities in the upper Tigris and Euphrates basins begin cultivating wild cereals and managing herds, coinciding with the site's later use.
Newer construction phases at Göbekli Tepe feature smaller rectangular structures with less monumental pillars, suggesting social or economic changes.
The monumental structures at Göbekli Tepe are intentionally backfilled with rubble, sediment, and debris, preserving them for millennia.
The buried mound remains untouched and largely unnoticed for thousands of years, appearing to later observers as an unremarkable hill.
A joint American and Turkish survey team notes the mound and its broken limestone slabs but interprets them as a medieval cemetery, not recognizing their Neolithic origin.
German archaeologist Klaus Schmidt recognizes the true age and significance of the site and launches the excavation that reveals it as the world's oldest known monumental architecture.
Enclosures built in this later period, such as those in Layer II, are more modest in scale compared to the grand circular enclosures of earlier centuries. Archaeologists interpret this shift as reflecting the transition of society away from large mobile hunter-gatherer gatherings toward smaller, more settled agricultural communities with different social structures and possibly reduced capacity or need for monumental communal labor projects.